The Waukivory Pilot Program gathered data from four natural gas wells drilled in 2012 at two properties near Forbesdale. The wells were drilled into the deep coal seams hundreds of metres below the surface and completely sealed off from surrounding rock layers and beneficial aquifers.

This information demonstrated how much water is produced from the coal seams, assessed the natural gas potential of the wells and determined the impact (if any) on overlying groundwater systems.

Following a review of the Waukivory Pilot gas flow data, economic modelling of gas reserves and market conditions, AGL announced on 4 February 2016 that it will not proceed with the Gloucester Gas Project.

AGL will commence an extensive decommissioning and rehabilitation program for its well sites and other infrastructure in the Gloucester region.

AGL has submitted a Review of Environmental Factors to the NSW Office of Coal Seam Gas to perforate, hydraulic fracture and flow test these wells. Activity will only begin once we have received the appropriate approvals.

The Review of Environmental Factors

AGL has lodged a Review of Environmental Factors (REF) application with the NSW Office of Coal Seam Gas to perforate, hydraulically fracture stimulate and conduct a production test from four existing wells drilled in 2012 at two properties near Forbesdale.

The REF was developed in line with the NSW Government’s Codes of Practice for Coal Seam Gas announced in 2012 and includes an independent environmental assessment.

The REF concludes that if the pilot project is implemented under current environmental standards and guidelines, and follows the recommendations and plans as set out in the REF, AGL’s environmental management plan, fracture stimulation management plan and water management plan; then adverse impacts are expected to be negligible or low.

AGL submits Supplement to Further Addendum - July 2014

AGL applies for Waukivory REF modification - April 2015

AGL has applied to the Office of Coal Seam Gas to vary its Waukivory REF approval to enable the movement of flowback water from the Waukivory Pilot site to a large, double-lined dam on AGL’s nearby Tiedmans property.

Hydraulic fracturing fluid

The ingredients used to make up the hydraulic fracturing fluid form a basic recipe determined by the geology of the target area and the desired fracture length, height and thickness.

Most hydraulic fracturing fluids used by AGL are simply sand and water. In fact, at least 98 percent of all fracture stimulation fluid is water.

Sometimes small amounts - usually less than 2 percent of the total volume - of commonly-used additives are included in the recipe. They are used to prevent bacterial growth, make it easier to pump the fluid into the coal seam and thicken the fluid so that less water is needed to carry the sand into the fracture. You can view the list of additives used in our Hydraulic fracturing fluid fact sheet.

After the completion of the hydraulic fracturing process, the fluids will be recovered as part of the dewatering process, and brought back to the surface for lawful disposal or beneficial reuse.

The specific additives proposed for use at the Waukivory Pilot are guar gum, hydrochloric acid, citric acid, acetic acid, THPS, sodium hydroxide, hemicellulase enzyme, choline chloride and monoethanolamine borate. Some common uses for these additives include washing powder ingredients, antiseptics and cosmetics.

AGL has conducted comprehensive risk assessments on all of the additives used in its fracture stimulations processes.

In compliance with the NSW Government’s Ban on use of BTEX compounds in CSG activities policy, AGL’s hydraulic fracturing fluid has been tested in an accredited laboratory and demonstrated to meet Australian drinking water health guideline levels. Those tests, conducted by a NATA-accredited laboratory in September 2014, confirmed there were no BTEX compounds detected in AGL’s hydraulic fracturing fluid. View the Certificate of Analysis here.

Waukivory Pilot well logs

AGL gathers extensive data on the Gloucester region’s geology. We document this data using well logs which show the type of rock at various depths in the well, how porous and dense the rock is and the natural background radiation levels.

We produce well logs for every well we drill.

We take rock samples at every few metres of depth to map the different layers of earth which enables us to identify the location of coal seams. We also use geophysical logging equipment to measure different properties of the rock.

In 2012, AGL drilled four pilot wells in the Waukivory region as part of our exploration activities for the Gloucester Gas Project. Each has a detailed well log.

The four Waukivory logs show the type of rock is largely sandstone, siltstone and coal, with typical background levels of radiation for that kind of rock.